US3026A-S08-R UTC [Unisonic Technologies], US3026A-S08-R Datasheet - Page 7

• Manufacturer Part Number: US3026A-S08-R
• Description: DUAL-CHANNEL USB POWER SWITCH AND OVER-CURRENT PROTECTION
• Manufacturer: UTC [Unisonic Technologies]

US3026A
conditions (such as UVLO, thermal shutdown and over-current) that appear will turn off the power switch, and the
FLAG pin will go low. Of course, the two internal FLAG circuits also operate respectively.
Input and Output
(Output) is the connection to the drain of the output MOSFET. In a typical application circuit, current flows through
the switch from IN to OUTX towards the load. If V
from OUTX to IN since the MOSFET is bi-directional.
Power ON and OFF
inrush-current from flowing through the switch from IN to OUTX towards to the load, while the high-capacity
capacitor is connected to the OUTX.
Thermal Shutdown
circuit. If device junction temperature rise above approximately 145 , both switches are turned off, both fault FLAG
outputs are activated, and they goes low. Hysteresis ensures that both switches turned off by thermal shutdown will
not be turned on again until the die temperature is reduced to 135 . When the thermal shutd
the output pins are in the OFF status. However, the UTC US3026A enters the standby status when EN pins are all
inactive.
Current Limit
caused by excessive currents. The current limit threshold is preset internally, If an over-current is detected, the IC
performs a slow-start operation again, it is assumed that output is short circuit, and FLAG pin will go low, FLAG
output is available to indicate fault conditions independently to the USB controller.
Under-Voltage Lockout
voltage drops below 2.2V (typical), UVLO shuts off the both output MOSFET switches and signals the FLAG.
Fault FLAG
conditions such as under-voltage, current limit and thermal shutdown. In a typical application circuit, the FALG pin
has a pull-up resistor of 10kΩ to input voltage.
The UTC US3026A is dual P-Channel switches with active-low and active-high enable inputs, respectively. Fault
IN (Input) is the power supply connection to the control circuitry and the source of the output MOSFET. OUTX
The UTC US3026A performs a soft-start operation on power application, which is to prevent an over-current or
The current limit circuit is designed to protect the output MOSFET, the load and the IC supply from damage
UVLO prevents the output MOSFET switch from turning on until input voltage exceeds 2.3V (typical). If input
The fault FLAG is an output with open-drain of N-channel. The fault FLAG is pulled down when any of the
The UTC US3026A is internally protected against excessive power dissipation by thermal shutdown protection
FUNCTIONAL DESCRIPTION
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
OUT
is greater than V
℃
℃
IN
when the switch is enabled, current will flow
own circuit is activated,
CMOS IC
QW-R502-086,A
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